The conjunctiva is the transparent membrane that protects the eye. When you look at the white part of the eye you are really looking through the conjunctiva at the sclera, the tough, wall of the eyeball. The conjunctiva has many small blood vessels running through it. The purpose of the conjunctiva is to lubricate and protect the eye.
Conjunctivitis is an inflammation of this lining of the eye. Conjunctivitis can be caused by a number of different things: bacteria, viruses (as in "pink eye"), allergies, chemicals, and more.
Symptoms of bacterial conjunctivitis may include eye redness, swelling of the lid, a yellowish or greenish discharge, irritation, itching and mattering of the lids. One or both eyes may be involved. The bacteria that most commonly cause conjunctivitis are Staphylococcus, Streptococcus, and H. Influenzae. Lab cultures are not usually necessary to make the diagnosis.
Antibiotic drops may be used if bacterial conjunctivitis is suspected. In severe infections, oral antibiotics may be necessary. Covering the eye is not recommended, because this can further incubate the germs. If left untreated, conjunctivitis can create serious complications, such as infections in the cornea, lids, and tear ducts.
The most common infection seen in the eye doctor's office is a viral conjunctivitis. Dozens of viruses can cause this type of infection. Sometimes only the eye is infected; at other times the eye condition is part of a more generalized problem, such as the "flu" or a cold. Both eyes are usually involved, but not always at the same time. Usually symptoms are mild and not serious. Once in a while, however, the eye complaints are incapacitating and extremely bothersome.
Symptoms of viral conjunctivitis include a wide range of complaints. Redness, tearing, swelling of the conjunctiva, and a clear discharge are characteristic. Light sensitivity can also be a prominent symptom. Sometimes a lymph node on the cheek in front of the ear swells in response to the virus, (this is an important clue that the patient has viral, not bacterial conjunctivitis).
If there is involvement in the cornea, blurred vision may result. Fortunately, this blurriness resolves over a few days to weeks and rarely leaves scars. Occasionally the lids may become swollen and the patient experiences serious eye pain, and rarely there is bleeding into the lids.
Treatment is aimed at making the patient comfortable during the first few days. Cool compresses soothe the eyes and lids, pain relievers help with discomfort, and occasionally eye drops will help; but the real treatment is time and rest. Viral conjunctivitis does not respond to antibiotics, but usually resolves within 1 to 2 weeks in most cases.
Since this disease is very contagious, prevention of spread is very important. Hand washing is very important to avoid spreading the germs. Direct contact with the infected eye should be avoided. Indirect contact through hand towels, wash cloths, and clothing should be carefully avoided. Complete resolution is expected in almost all patients.